I have a pair of Energizer Hi-Energy Lithium batteries that I think
are a pile of junk (to be polite). I don't believe they gave me any
more battery life than a set of regular alkaline batteries.
Nearly.
(compared to AA size alkalines)
By looking at the specs, under "normal" conditions, you're looking at an
about 50% increase in capacity, for about a 300% increase in price.
In practice, you're likely to see much the same.
Where they come into their own, is abnormally low temperatures (near
freezing in the snow for instance), where their life is about 10x alkalines.
Another area they may be better in is shelf life. You can expect about 10+
years for lithiums, and about 5-7 for alkalines.
Another perhaps fringe improvement is mass. They are generally lighter than
alkalines.
So if you're only ever in relatively warm climates, chew your batteries in
less than a few years, and don't care your saving a few snots worth of mass,
then they're largely pointless.
Otherwise in the above mentioned conditions, they can present a useful life
time increase, (albeit at some cost).
One point to be careful of, we have the e(squared) (e2) titanium batteries
here in australia. I'm guessing they're all over the world too.
I've never tried them, but going on the specs, they offer zero improvement
over the more "standard" alkaline batteries. At a premium of at least 150%
cost of the same-branded alkaline batteries.
There are minor differences of course, but nothing that you're going to
notice under use.
Their selling point is "improved" performance on high-current devices. True
to their word, they aren't lying (technically). However, you'd better get
your stop-watch and calculator out if you're going to note any differences...
And, they
are not rechargeable according to the fine print which is in red print
on a gold background so that it is impossible to read unless you use a
magnifying lens and a very strong light.
It's a PRIMARY battery technology. They were never designed to be
recharged. Same with alkalines. They were NEVER designed to be recharged.
The fact they ARE recharged is that someone (many years ago) found a charge
technique that doesn't fry the battery while still injecting some useful
energy back into it (albeit with some conditions attached).
Rechargeable alkalines have modified chemistry that tries to improve the
recharge life (which was less than a dozen times) at the cost of other
performance points. (along with a corresponding increase in price which makes
standard secondary rechargeable technologies look attractive).
IMO, get over it. If you want a rechargeable, buy a rechargeable (NiCAD/NiMH).